Def. pub.
preparation op metal composites having an encapsulated
inner layer and composite metats produced thereby



7 we DEFENSIVE PUBLICATION UNITED STATES PATENT OFFICE Published at the request of the applicant or owner in accordance with the Notice of Apr. 11, 1968, 849 O.G. 1221. Identification is by serial number of the application and the heading indicates the number of pages of specification, including claims, and of sheets of drawing contained in the application as originally filed. The file of this application is available to the public for inspection; reproduction may be purchased for '30 cents per sheet.

Applications published under the Defensive Publication Program have not been examined as to the merits of alleged invention. The Patent Office makes no assertion as to the novelty of the disclosed subject matter.

PUBLISHED MARCH 25, 1969 Three-layered products, preferably planar or tubular, which are useful as electrodes in corrosive electrolytes, comprise like outer layers of titanium, zirconium, tantalum or niobium, and an inner layer of copper, aluminum or iron that is bonded to each outer layer over substantially their entire interface by a metallurgical bond consisting essentially of direct outer layer-to-inner layer (explosion) bond and is encapsulated (to the extent required to protect it from corrosion) between overlapping portions of the outer layers by a continuous metallurgical seal that is of the same composition as the outer layers and bridges their overlapping portions. Products such as titanium/ copper/ titanium having a completely encapsulated copper layer are particularly useful as electrodes in electrolytic copper refining and chlorine reduction cells. The above products are prepared from three-layered explosionbonded composites by selectively removing metal from the exposed surface(s) of the inner layer, e.g., by machining or chemical etching, thereby recessing the inner layer between overalpping portions of the outer layers, and then fusion bonding, e.g., by TIG welding, the overlapping portions directly to each other or to a like metal insert that has been positioned in the recess between the overlapping portions.

arch 25, 1969 s. s TOR DEF. PUB.

PREPARATION OF METAL COMPOSITES HAVING AN ENCAPSULATED INNER LAYER AND COMPOSITE METALS PRODUCED THEREBY Filed Dec. 11, 1967 w v H M 1 M. I u 4 A T\V w 3 3 P r .w .I /4 Z r F a W .4 .M I 6 a .0 a a 3 2 FIE/K3 4L/ a a v 5 N3 5 2,1 F /.V a IV A 2 z w, 7 O v v F N 6 0 v F 6F a F F W 6 9w INVENTOR. U SADUN S.TOR 

